At shortly past 5 a.m. on workdays, Jeff Zgonina parks his Ford F-350 pickup in the Houston Texans' players lot outside Reliant Stadium. He enters the building by tapping an access code into a backdoor keypad, walks into the locker room in darkness and slides the folding chair out of his dressing cubicle, the professional athlete's equivalent of punching a time clock. "When everybody else comes to work here," says assistant trainer John Ishop, "Jeff's chair is already out." A routine unfolds: hot tub, weight room, breakfast (strawberries, pineapple and cottage cheese). Before 7 he's sitting in the equipment room, busting stones with the help and watching teammates arrive.

Zgonina is 39, the second-oldest nonkicker in the NFL. The oldest is Brett Favre, and on that sliver of common ground the resemblance ends. Zgonina has played 17 seasons on the interior defensive line and special teams for eight franchises, including five years with the Rams, four with the Dolphins and seven days—during a bye week, no less—with the Raiders in October 1998. He has started just 63 of his career 208 games, and he has never been paid more than the NFL minimum (currently $860,000) for a season's work. Few players have endured more kickoff return-team collisions, of which, says Zgonina, "half the time you just get run over by a missile."

The NFL is larger than life, an unscripted weekly drama with celebrity superhero stars. You know their names. But if they are the face of the sport, Zgonina is the soul. He is a nearly middle-aged man with a 6'2", 290-pound body shaped like a refrigerator on feet, a rare unselfish passion and a throwback philosophy that NFL status should be earned rather than bestowed on draft day. He has lived in hotels for entire seasons when he barely played a down, and he has been on the field for the final snap of a Super Bowl victory.

Three times Zgonina has been cut from rosters at the end of training camp, and at least a half-dozen other times he has survived that last cut while waiting by the phone. "A lot of guys feel like they're going to play forever," says Zach Thomas, the five-time All-Pro linebacker who played with Zgonina in Miami from 2003 to '06. "Jeff always feels like the team is going to cut him. He doesn't take the game for granted for one day." Zgonina has never been a star, but he has left deep footprints in the locker room of every team for which he has played, providing a heavy dose of daily professionalism and demanding the same from his peers. He has officially missed one game in 17 years due to injury, a broken finger in the last week of 1997.

"Football is full of hard-asses," says Kevin Carter, a former All-Pro defensive lineman who played with Zgonina for five years in St. Louis and Miami. "Some guys are hard-asses because they're overly talented. Some guys because they've had some difficult experience in life. And others are hard-asses because they know what it's like to do all the dirty work. Jeff is a hard-ass in that respect because he had to go through a lot just to play this game. But he is also the most salt-of-the-earth guy I've ever known."

In his 17th autumn, Zgonina (pronounced ska-NEE-na) is getting 20 to 30 snaps a game at the nose and defensive tackle for Houston, alongside the likes of Amobi Okoye, who was born during Zgonina's junior year at Carmel High in the Chicago suburbs. Texans general manager Rick Smith, a friend of Zgonina's since they were teammates at Purdue two decades ago, signed him to a two-year contract in 2007 but initially wasn't going to bring him back for '09. "I didn't think he could make our team," says Smith, "and I didn't want to have to cut him."

Throughout the off-season, Zgonina pestered Smith about coming back. "Rick told me he didn't want to cut me," says Zgonina. "I told him, 'You think if you cut me we won't be friends anymore? It's business; if anybody understands that, it's me. All I'm asking is, if you cut me, take me out and do it over a beer.' In the meantime I'll play all the preseason games and I'm on tape for 31 other teams to see."

Not that Zgonina was full of confidence. He would run and train in the summer heat—sometimes alongside his wife, Cammie—and ask himself, What am I doing? Maybe it's time for a new chapter. Nine years ago Zgonina and Maury Tate, a former calf roper, started a company that raises bucking bulls for rodeos. (The company is called The "Mo" Betta Bull Company because Tate already owned a handmade Western shirt company called the "Mo" Betta Clothing Company, whose products have been worn by Garth Brooks.) They own more than 100 bulls for competing and breeding. Maybe it was time to run full time with the bulls.

But when defensive tackle Travis Johnson was slow to recover from hernia surgery (he was eventually traded), Houston needed a body, and Smith signed Zgonina on the eve of training camp. "I told Jeff he was going to have to take every rep in practice and play in the fourth quarter of preseason games, which you just don't do with a veteran player," says Smith. "Of course, once he gets in here he's one of those guys who is almost impossible to cut."

Zgonina wasn't so sure. His mother, Donna, comes to most of his games, and before the preseason finale, at Tampa Bay on Sept. 4, Jeff called and said, "Mom, this might be the last time you watch me play." A day later, as the Texans made their final cuts, Zgonina was grocery shopping with Cammie, and their children, daughter Bailey, 6, and son Carter, 3. Defensive line coach Bill Kollar—who recruited Zgonina to Purdue as a high school senior—called Jeff's cellphone and said, "Just be here tomorrow."

Zgonina rewarded the Texans in Week 2 when he sealed a 34--31 victory over Tennessee by recovering a Kerry Collins fumble with 1:32 to play. "On the bottom of the pile it was me and Kerry and [Titans center] Kevin Mawae," says Zgonina. "That was about 50 years of experience fighting for that ball." His performance on Oct. 4 in Houston was a typical day's work: Three tackles off the bench, a sack of JaMarcus Russell and one very professional seal block on Jacoby Jones's 95-yard kickoff return in a 29--6 win over the Raiders. On Sunday at Arizona he was credited with one tackle in a 28--21 loss.

Spotlight moments are rare for Zgonina, who will leave behind a legacy of quiet, selfless contribution. How does a man survive 17 anonymous seasons in the NFL? "Timing, luck," says Zgonina, "and when you get the chance, you ball out and play hard. Maybe they'll keep you."

Those things, and more.

"Almost anybody playing at his age has to be a little bit of a freak," says Kollar, who has coached Zgonina at Purdue, Atlanta, St. Louis and now Houston. "You'd like for everybody to be All-Pro and tear it up out there, but there aren't many of those. Jeff is a true pro. He studies hard, works hard, plays hard. And on Sundays he's still hard to move off the ball."

At every stop in his career Zgonina has been regarded as a unifying locker room force, less through cheerleading than through gruff, old-school ballbusting that could border on hazing. "When I was a young player, I was Zgonina's and [fellow veteran] Jeff Robinson's whipping boy," says former defensive end Grant Wistrom, who signed with the Rams for $12.7 million as the sixth pick overall in the 1998 draft. "They called me a bust every day. I was like Private Pyle in Full Metal Jacket. Couldn't do anything right. The coaches tell the veterans not to haze rookies, but I made more money with one swipe of the pen than maybe Jeff Zgonina has made in his entire career. I deserved to get hazed. And it made me a better player. Jeff is one of the best people I've ever known in the game."

Zgonina says, "Grant worked his ass off. But I've seen of plenty of rookies, and free agents too, who get a lot of money and think they're God's gift. When I first came into the league, you had to earn your playing time. Now with a lot of guys, there's not a lot of earning going on."

Zgonina's attitude has tangible benefits. Young players follow him like puppy dogs into film sessions. "He's seen everything any offense can do," says third-year Texans defensive tackle Tim Bulman, 26. "In the film room he knows plays before they happen. I pick the guy's brain."

Kevin Greene, a two-time All-Pro linebacker and end who played with Zgonina in Pittsburgh in 1993 and '94 (Greene's wife cooked dinner for Zgonina once a week for two years) and coached him in two other spots, says, "Dude is not physically talented, but he's got a big heart, a big work ethic and a huge presence in the locker room."

That presence could be described as tough love, except that it's a whole lot tougher than loving. In the daily verbal sparring, Zgonina's path is best crossed with great caution and at great risk. "He's like the old man in the barbershop," says Thomas. "You can't let him know your weakness, because he will take you right down. I tried a couple times, and it was over fast."

Wistrom says, "For such a big, tough guy, he's like a little girl when it comes to gossip. He knows everything about everybody, and he'll use it against you in a heartbeat."

None of this would be of any significance at all if Zgonina couldn't perform. He was a high school star, a 250-pound defensive end, nosetackle, offensive guard, tight end and fullback. (His father, Casimir, who started and ran his own printing company, Uni-Label & Tag in Elk Grove Village, Ill., was a guard at St. Ambrose College in Davenport, Iowa; his sisters, one older and one younger, have both run marathons.) In the fall of 1988, Purdue gave him number 40 and decided he could lose 20 pounds and play linebacker. That lasted one painful year before he moved inside on the line, where he has remained for more than two decades.

On an athletic level, Zgonina has endured not just through the good fortune of roster openings and health (although both have been factors), but also through the pure reliability of his play. Packers defensive coordinator Dom Capers, who coached Zgonina in Pittsburgh, Carolina and Miami (and cut him at the first two), says, "He's smart and a great technician. There's a high comfort level having him on your team. He does what he's supposed to do."

Zgonina appears to be blocky and immobile, an interior stalemate machine taking on double teams. In reality he's effective at flowing with traffic and cluttering an opponent's running attack, and the modern game has met him halfway. "There was a time, maybe 10, 15 years ago, when they just wanted size on the defensive line," says Kevin Carter. "That didn't suit Jeff, because he wasn't 6'6", 350. Then defenses started priding themselves on 11 guys running to the ball. That was Jeff."

He's also been witness to a generation of NFL history. Zgonina was drafted in the seventh round by the Steelers in 1993, and on the first day of training camp he found himself in a team ritual called the Oklahoma Drill. (Elsewhere it's known as the Nutcracker.) "An offensive lineman and a running back on one side, a defensive lineman on the other side," says Zgonina. "I check the list in the locker room, and I'm going against [six-time All-Pro center] Dermontti Dawson and [All-Pro running back] Barry Foster. They blow the whistle, Dermontti stands me up, turns me and Barry just runs right on by. Awesome. I barely saw him."

Three years later Zgonina was playing half a season in Atlanta when, in the same game, he got his first career sack, on Steve Young, and later tackled Jerry Rice on a crossing pattern. "I was in a zone [blitz], and he came across the middle with the ball," says Zgonina. "He tripped over my arm."

Zgonina stuck with St. Louis in 1999 and was an important defensive reserve on the Dick Vermeil--Mike Martz--Kurt Warner team that beat the Titans 23--16 in Super Bowl XXXIV. In that game Zgonina was rushing against Hall of Fame guard Bruce Matthews when Steve McNair's completion to Kevin Dyson came up one yard short of the goal line on the final play, giving the Rams their first Super Bowl title. "Bruce was a great, great player," says Zgonina. "I came off the ball on that play, and he just clamped me and I was done. Then we both ran down to the goal line." (More six degrees of separation: Zgonina played with Matthews's brother, Clay, on the Falcons in 1996, and now he's in the league with Clay's son, also named Clay, a rookie linebacker for the Packers.)

Zgonina got his first start on Sept. 10, 2000, against Seattle, when St. Louis's D'Marco Farr was out with an injury. It was his eighth season and 66th game. Zgonina's father, acutely ill with pancreatic cancer, watched from the stands at Husky Stadium. He died 17 days later.

Zgonina lasted that season and two more with the Rams, terrific years in which he married Cammie, was close to his family home in Chicago and near the hunting and fishing that he loves. The next four seasons in Miami were nearly as good, as he played on a defense stocked with other elder statesmen—Carter, Thomas, Vonnie Holliday, Jason Taylor, Keith Traylor, Junior Seau. "I'd be lined up, and Junior would yell, 'Move over,'" says Zgonina. "He knew where the play was going, and he wanted to shoot the gap. The guy was incredible."

Thomas says of Zgonina, "Jeff was so unselfish. He made linebackers better."

Zgonina treats his daily routine—and especially his Sunday routine—with a reverence usually reserved for religious customs, a measure of his zeal for the game. "Or," he says, "I'm just a nut job."

His shoes are old-school high-tops that he stockpiled when Nike stopped making them several years ago. "They look old enough to go straight to the Hall of Fame," says Jay Brunetti, Houston's director of equipment services, a 35-year NFL veteran. On the bottom of the shoes Zgonina will wear only all-black cleats, unlike his teammates' glitzier models. His belt cinches with two metal rings, old school, while his teammates' have conventional buckles.

On Sunday mornings Zgonina is the only Texan who applies his own tape to his shoulder pads, and he uses ancient, four-inch carpet tape. (Other players' pads are taped by the equipment staff with thinner, two-sided tape.) Two blueberry cake doughnuts must be placed in his locker before the game by Brunetti's assistant, Chris Snell. When the team returns to the locker room for last-minute preparations, Zgonina sneaks into the equipment room and calls his wife. Upon returning to the field, he first smacks every assistant coach on the butt with the back of his right hand, then takes a seat on the bench at the 50-yard line, where Snell unties and then reties Zgonina's cleats before putting two puffs of air—not one, not three—into his helmet liner.

At the last minute Zgonina seeks out the second-oldest position player on the roster—with the Texans it's now 34-year-old strong safety Nick Ferguson—and says into his face, "Let's go, old man."

Soon the rituals will end. Zgonina says this is his last year. (Although he also says, "Never say never.") He will dote on his family, and he will devote more time to his bull-breeding business. An era will end as quietly as it has been played. And the game will lose a keeper.

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Zgonina has endured through pure reliability. He does what he's supposed to do.

Zgonina says this is his last year. He also says, "Never say never."

"Zgonina could play in any era of the game. He would fit right into the NFL of the 1920s or 1930s. And he fits now too."

FORMER NFL COACH JIM HANIFAN

At every stop Zgonina has been a unifying locker room force.

1995 STEELERS

1996 FALCONS

1998 COLTS

2002 RAMS

2005 DOLPHINS

2009 TEXANS

PHOTOPhotograph by ROBERT SEALEPHOTOGREG NELSON

WISDOM OF THE AGES A seventh-round pick in 1993, Zgonina (92) sets an example for his younger—and more highly compensated—teammates.